The low ground clearance is an issue. But I don't think traction will be.4motion = VW
4MATIC = MB
I would say the 45 would be a bear in the snow because it has way too much power and torque and super-low ground clearance. Even with excellent winter tires, I think it would not be good.
With winter tires and a torque vectoring AWD you should be able to get traction if you drive reasonably.
If you look at it this way. Subaru WRX STi. Lots of power. AWD. Even though the AWD system is different. They do great in the snow.